Level 94 Sage gets this quest to kill Hammerhand Patriarchs to get 5 Orb of the Rebel.

I know where they are located - at the far bottom of the Seat of Torment.

We battled our way in there but found the door was closed just south of the lowest bridge.
We could not find any nearby monster to kill that would open the door. In the end we ran out of time and exited with the quest unfinished.

We wined it but I believe that doesn't effect us being able to complete the quest.

Can anyone name or describe the guardian that opens this door?

*bump*
I would really appreciate any advice on this Hero quest called "Orb of the Rebel".
In case anyone doesn't recognise the name but would recognise the area, this is the situation again:

We have a quest to collect 5 Orbs of the Rebel which are a drop from Hammerhand Patriarchs. These monsters are located at the very bottom of the Seat of Torment sage fb99 map.
http://www.pwdatabase.com/pwi/mob/9243

At the entrance to this leg of the map there is a shimmering door. Unlike all the other doors on the map we were unable to find a guardian that opened it.

Does anyone know were or what the mob looks like?

Wondering this myself, any word?

you need to kill torturess venerator to open gate to the boss where hammerheads are best of luck